In a current communications system, user equipment (User Experience, UE) may simultaneously access a plurality of cell groups. Different cell groups may have transmission subframes of different time granularities. For ease of description, an example in which the UE simultaneously accesses a first cell group and a second cell group is used for description. The first cell group is corresponding to a first transmission subframe. The second cell group is corresponding to a second transmission subframe. The first transmission subframe and the second transmission subframe have different time granularities. When the UE transmits data to a base station, the UE adds to-be-transmitted data to the first transmission subframe and the second transmission subframe, allocates first transmit power to the first transmission subframe, and allocates second transmit power to the second transmission subframe. The UE transmits, by using the first transmit power, channel information on the first transmission subframe to the base station; and transmits, by using the second transmit power, channel information on the second transmission subframe to the base station.
A first transmission time of the first transmission subframe may overlap with a second transmission time of the second transmission subframe. In this case, the UE determines, from the first transmission subframe and the second transmission subframe based on the first transmission time and the second transmission time, a transmission subframe whose transmission time is earlier and a transmission subframe whose transmission time is later; and preferentially allocates transmit power to the transmission subframe whose transmission time is earlier. On the transmission subframe whose transmission time is later, the UE can use only reserved transmit power.
The prior art has at least the following problem:
If a time granularity of a transmission subframe whose transmission time is earlier is less than a time granularity of a transmission subframe whose transmission time is later, one transmission subframe whose transmission time is later is corresponding to a plurality of transmission subframes whose transmission times are earlier. When there is not always to-be-transmitted data on the plurality of transmission subframes whose transmission times are earlier, idle transmit power on the transmission subframes whose transmission times are earlier cannot be re-allocated to the transmission subframe whose transmission time is later, thereby causing waste of power resources and low power utilization.